Do dense breasts affect my risk of getting breast cancer?

Yes. Dense breasts not only can hide cancer on a mammogram, but they also increase the risk of getting breast cancer. Cancers grow more often in dense tissue than in fatty tissue. The denser the breasts are, the higher the breast cancer risk. Women with the densest breasts (“extremely dense”) are 4 times more likely to get breast cancer than women with the least dense breasts (“fatty” breasts). Most women’s breasts have density in between these two categories (“scattered fibroglandular density” or “heterogeneously dense” breasts).

What are risk factors for breast cancer?

Most breast cancer occurs in women with no known risk factors other than being a woman and getting older. There are many risk factors that increase the chance of getting breast cancer. For example:

• Having dense breasts
• Having a family history of breast or ovarian cancer (particularly in your mother or sisters)
• Having an atypical breast biopsy (where breast cells from a small sample of your breast tissue were not normal, but not yet cancer)

Visit “Is My Mammogram Enough?” for more information.

Learn More:

• 5 Facts Every Woman Should Know
• Video Series: Let’s Talk About Dense Breasts
• Patient Risk Checklist (print)
• Patient Questions and Answers